Monday 16 March 2020

Far Eastern Acute Respritory Syndrome (F.E.A.R.S).

That is the name I have given to this current Coronavirus.

Primarily because it will make people on TV sound like they've got a stutter. At a time they're trying to be all serious.

One thing is for sure though. We have got to stop referring to it as; "Coronavirus." That is an almost entirely redundant name.

Coronavirus is not a single virus but a sub-group of viruses. Rather like how humans are a sub-group of mammals.

The name comes from the way that all viruses in the family appear under an electron-scanning microscope. This produces a two dimensional image of the viruses nucleus surrounded by a Laurel, Crown or Corona of protein spikes in a circle.

The Coronavirus family is actually one of the largest group of viruses in the World. It contains an almost infinite number of individual viruses.

Many Coronaviruses have absolutely no effect on humans whatsoever. At any given point there is a good chance that you are infected with a couple of Coronaviruses. However you have absolutely no idea because they have absolutely no effect on you.

One of the most widely known Coronaviruses is the Common Cold. People often ask why modern science still hasn't been able to cure the Common Cold.

The reason is that each year the Common Cold is caused by a new or "novel" Coronavirus. Rather than catching the same illness year after year people are actually catching a whole new illness each year.

In fact the Common Cold is often caused by a cocktail of several novel Coronaviruses all infecting the body at the same time. Normally with a couple of bacterial infections thrown in for good measure.


The Virus.

The specific Coronavirus people are concerned with at the moment is; "2019nCoV." That is to say the Novel (n) Coronavirus (CoV) which was discovered in 2019 (2019).

2019nCoV lives in and is spread by minute water droplets carried in people's breath and through the air. These are the things you can see when you breathe directly onto glass or a mirrored surface.

This means that the virus normally first enters the body through the respritory tract. Everything from your mouth down, through the throat, to the tiny aveloei, air sacks in your lungs.

Once inside the respritory tract the protein spikes on 2019nCoV start latching onto the cells. Effectively hijacking them to suck out the protein which provides the fuel 2019nCoV needs to reproduce. This stops those cells from working properly and doing the job they are supposed to.

At the same time the immune system reacts. Essentially going to war with 2019nCoV, dispatching antibodies to kill the virus cells.

The symptoms you typically associate with being ill - fever, muscle fatigue, that groggy feeling etc - are often actually caused by the immune system. At the celluar level this immune response causes healthy cells to become inflammed. Reducing their ability to function properly.

This battle between healthy cells, 2019nCoV and antibodies produces lots of casualties. Cells of all types which die and are shed.

That sounds dramatic. However the human body is one long, continuous process of cells dying, shedding and being replaced by new ones.

The Half-Time Show of the 2020 Super Bowl saw us all talk extensively about menstruation. This is the monthly process of the cells lining the uterus dying, shedding and being replaced with new ones.

Household dust is made up of a surprisingly large amount of human skin. Skin cells are constantly dying, shedding off the body into our carpets and being replaced by new ones.

During a viral infection though this process happens much faster and in greater numbers. Meaning that the dead cells pile up faster than they can be cleared away. This produces the sputum or phlegm that you're all familiar with from being ill.

That build up of dead cells obviously takes up space within the lungs. Space which then cannot be used for the lungs normal function.

The Illness.
 
Those three factors combine to reduce the lungs ability to do their main job. Drawing Oxygen into the body and expelling Carbon Dioxide.

This can cause a number of knock-on effects elsewhere in the body.

Obviously the first area to be affected is the Respritory System itself.

With the lungs not drawing in enough Oxygen the body compensates. By taking more frequent breaths. With lung capacity reduced by inflammation and sputum build up breaths also often become shallower.

That forces the muscles, diaphragm, intercostal etc,which inflate and deflate the lungs to work much harder. The difference between walking at 6kmph or running at 16kmph. Like all muscles anywhere else in the body this can cause them to become fatigued and ultimately tear.

The second area to be almost immediately affected is the Cardiovascular System. The heart which pumps blood and all the tubes that carry blood around the body.

With less Oxygen entering the blood from the lungs the heart has to start moving more blood around the body. In order to maintain the same Oxygen level. This forces the heart to work much harder. Like all muscles anywhere else in the body this can cause the heart muscle to become fatigued and ultimately tear.

Tearing one of your hamstring muscles is painful. Tearing your heart muscle is normally pretty fatal.

The haemogloblin cells which carry Oxygen within the blood function almost exactly as tiny little ballons. They get blown up with Oxygen at the lungs. Travel inflated through the bloodstream and then deflate at another organ in the body.

Reducing the amount of Oxygen reduces the pressure these cells are inflated to. That changes the pressure throughout the circulatory system. Placing unusual demands on the pipes and valves. Increasing the chances that they will weaken and tear.

If one of the capillary tubes in your brain tears then you are having a haemorrhagic stroke. Like a tear in the heart muscles that almost instantly becomes a very serious problem. One which often results in death.

If the respritory and cardiovascular systems are not able to compensate for the reduced Oxygen intake then all the vital organs of the body stop getting the Oxygen they need to function. This means that they will be less able to do their job and ultimately could die.

I should point out though that most of the body's vital organs have far more capacity than they actually need. For example most people have two kidneys. You only really need about a quarter of one.

The human body is also extremely good at prioritising. So it will stop your fingernails from growing long before it shuts down your brain.

However once the function of vital organs starts to be reduced it starts causing another range of knock-on effects on the body.

For example the kidneys and liver primarily clean toxins out of the blood. As they become less able to do that the blood starts becoming clogged up with toxins. Increasing things like dehydration. Depriving cells already short on Oxygen of the fluid which is also vital to their function.

This all increases the risk of Sepsis.

Sepsis is somewhat like the immune system going into a mad panic. Rather than attacking viruses and toxins it just starts randomly attacking everything. Killing off healthy cells in vital organs, further weakening them.

It also often sees the immune system burn out and switch off. Leaving all the viruses and toxins to go about their business unchallenged.

Together these knock-on effects of infection of the respritory tract are known as; "Acute Respritory Syndrome (ARS)." Or; "Severe Acute Respritory System (SARS)." Depending on how severe the symptoms become.

The specific SARS caused by 2019nCoV is; "SARS-CoV-2." As in; Severe Acute Respritory  Syndrome (SARS) caused by Coronavirus (CoV) - Variant 2 (2). Some of you may remember the 2002 outbreak of SARS-CoV-1. Which is known commonly as simply; "SARS."


Treatment.

The symptoms of SARS-CoV-2 obviously sound serious and frightening. However there is a vast range of very simple things which can be done to control and mitigate them while the body fights the infection. This is known as supportive treatment.

At the most simple the air which we typically breathe is not made up of 100% Oxygen. People can quite easily be provided with pure Oxygen. Normally through a little tube sitting just below the nostrils. This increases the amount of Oxygen in each breath. Reducing the amount of work the lungs need to do.

If that doesn't work it is quite easy to provide someone with Oxygen under pressure. Normally though a facemask. This forces pure Oxygen into the lungs. Further increasing the amount of Oxygen in each breath. Reducing the amount of work the lungs need to do.

If that doesn't work the patient can be hooked up to a ventilator. This forces air/Oxygen into the lungs and sucks Carbon Dioxide out. This takes much of the workload off the lungs and the muscles which inflate and deflate them.

If that doesn't work then the respritory system can be bypassed almost entirely. By inserting a tube down the throat and into the lungs. The other end of that tube is connected to a ventilator which forces Oxygen into the lungs and sucks Carbon Dioxide out.

If one of the tubes carrying blood bursts. Then a surgeon can go in and seal it back up again. Or insert another tube which bypasses the tear.

If the kidneys stop working. Then the patient can be hooked up to a dialysis machine which will clean the toxins from the blood.

If the immune system goes haywire and starts attacking everything. Then drugs can be administered to calm it down.

Some of you may remember the Jai McMath case from the US in 2013. Others can use search engines.

So-called "Lazarus" cases such as that show that it's no longer really a question of whether medical professionals can do all these things to keep people alive. It's really more of a question of whether ethically they should in cases where the patient has no chance of recovery. 

That is how good the medical profession has become at this sort of thing. Since something like the 1918 Spanish Flu pandemic.

Testing.

The distinction between the virus (2019nCoV) and the illness (SARS-CoV-2) brings me onto the issue of testing. I know that particularly in the US this has become a very political issue of great concern to many people.

However in clinical terms, looking after patients, testing is almost completely irrelevant.

For example if you've tested positive for the virus bu't don't have any of the SARS symptoms. Then essentially you've won. This thing everyone's so worried about has attacked you and had absolutely no effect.

Your biggest worry now is your government calling on you. To go out and start licking random strangers. In order to spread your antibodies far and wide.

Likewise if you are experiencing SARS symptoms but haven't tested positive for the virus that really doesn't matter. Rather than treating the virus medical professionals treat the SARS symptoms.

The way those SARS symptoms are treated are exactly the same regardless of what is causing them.

The way your treatment progresses will be based on the progression of the symptoms. Measured by a host of other tests. Primarily on lung function and the amount of Oxygen within the blood.

Where testing is vitally important is in research and surveillance. How the virus behaves in the human body and how it behaves in the population generally.

To give you an idea why this area is so important 2019nCoV initially had a 100% mortality rate. It killed everyone it infected.

In the sense that we only started looking for it because 44 people had died. We needed to explain why.

From those 44 the Chinese quickly identified the virus and developed a test for it. Although nucleic acid tests are pretty standard these days.

This allowed researchers to start collecting much more data about 2019nCoV. Giving a much broader and, thankfully reassuring, picture of what it is and what it does.

On February 17th (17/2/20) a study of that data was published. By lead author Yanping Zhang. Although it only looked at 44,672 laboratory confirmed cases this is the largest and really only clinical study into 2019nCoV which exists at the moment.

It showed that rather than dying 81% of those infected showed only mild symptoms. The groggy feeling, fatigue and slight cough that you're all familar with from being ill.

A further 14% of those infected experienced severe symptoms. Which I'll agree sounds severe. It's even got the word; "Severe" in there.

However what are considered severe symptoms in the study are not actually that severe.

A few years ago I accidentally made and exposed myself to Chlorine Gas. This caused me to experience laboured, shallow breathing. An erratic heartrate and, I assume, a drop in Oxygen levels in my blood.

It also caused coughing. A lot of coughing. To the point that the coughing caused hiccups. Trying to hiccup and cough at the same time is certainly an experience.

If those symptoms had been caused by 2019nCoV rather than Chlorine Gas, and my own stupidity, then I would be classed as severely ill.

However I really wasn't severely ill. I didn't require any medical treatment. It was just a matter of waiting a couple of days while my body neutralised the Chlorine.

Those particular symptoms do cause an interesting bio-feedback loop though.

When your brain panics it tells the lungs to start taking shallow, laboured breaths. When your lungs start taking shallow, laboured breaths for another reason it convinces your brain that it should be panicking. So it does and starts telling your lungs to start taking shallow, laboured breaths. Trapping you in a vicious cycle.

In my experience I've found it's important to remember that is just panic. Panic doesn't kill people. It just causes them to make bad decisions.

I suspect though that my plan to start forcibly drown-proofing the general population might be rejected by the ethics board.

Of the 44,672 patients in the Chinese study 4.7% epxerienced critical symptoms. These are very serious. Things like Respritory Failure, Sepsis and multiple Organ Failure.

However of the 2,087 patients who became critically ill only 49% died. The other 51% survived those serious symptoms.

Risk Factors.

There is an old saying in medicine that statistics mean nothing to the individual.

So despite the indications from the Chinese study it doesn't mean that for every 100 infected people 81 will have only mild symptoms and 3 will definitely die.

There are other risk factors which determine how 2019nCoV will affect you.

The main one these seems to be Age.

Rather like your car the longer you've had your body and the more you've used it the more likely it is the parts will wear out and break. So while the study shows infection peaking in the 40-49 age range mortality increases with age as infection rates fall away.

The study also shows Cardiovascular Disease to be a main risk factor.

Of the 875 patients with both 2019nCoV and Cardiovascular Disease 10.5% (92) died. I think we can also add to that group the 6% (161 of 2,683) of patients who died suffering from both 2019nCoV and Hypertension.

There are a host of things that can cause Hypertension (High Blood Pressure). Stress, a high salt diet, kidney disease. However Cardiovascular Disease is one of the main causes of Hypertension.

That Cardiovascular Disease and Hypertension are significant risk factors for SARS-CoV-2 is hardly surprising. It's well known that any form of SARS puts considerable extra pressure on the Cardiovascular system. If it is already weak to begin with it is going to be less able to withstand that extra pressure.

Likewise it's not surprising that Chronic Respritory Disease is also a major risk factor.

Of the 511 patients with both 2019nCoV and Chronic Respritory Disease 32 (6.3% died). We know SARS affects the respritory system. An already weakened respritory system is going to be less able to cope.

The picture with another major risk factor identified - Diabetes - is less clear. The health complications caused by Diabetes is a vast topic. However looming large amongst them is Cardiovascular Disease.

So I think it is reasonable to assume that of the 1,102 patients with both Diabetes and 2019nCoV were actually suffering from undiagnosed Cardiovascular Disease. Something which is probably true of the 80 (7.3%) who died.

Likewise the final major risk factor identified - Cancer - is another extremely broad topic. Possibly referring to almost every area of the human body.

Given that this is a respritory disease I think we can assume that someone suffering from Lung Cancer is at much greater risk. Compared to someone suffering from something such as Breast Cancer.

Also cancer treatment is extremely aggressive. It relies on using toxic chemicals or radiation to kill off the body's cells. The hope being that it kills the cancer cells before it kills all the other cells and the patient.

So I think it is reasonable to assume that someone who is undergoing treatment for Breast Cancer is at a higher risk. Compared to someone who is in remission from Breast Cancer.

If you have been diagnosed with any of those conditions then you will already be under the care of a Doctor. I strongly recommend you discuss it with your Doctor.

They will be far more knowledgeable about the specifics or your condition and significantly more qualified than I am.

Excluding age without those added risk factors the study shows the mortality rate for 2019nCoV infection dropping to just 0.9%.

There is also good reason to suspect that the Chinese study may paint a slightly more pessimistic picture than average.

Firstly China is a Communist country. However it does not have a socialised healthcare system. Instead relying on private health insurance. Although it has increased signficantly since the 2002 SARS-CoV-1 outbreak China is still very far away from having universal healthcare coverage.

Also where it is available China is still very much a developing country in terms of healthcare. With standards of care being significantly lower than in developed nations such as the US or Europe.

In the US or Europe a Doctor is just that. A person who holds a PhD in medical science. That means they've spent three years obtaining a Batchelor of Science degree. A further year obtaining a Master of Science degree. Then a further one to two years obtaining a PhD. All before undergoing clinical training.

In China Doctors often only hold the Batchelor's degree.

That is in the urban areas. In more rural areas China still uses what are known as; "Barefoot Doctors."  Essentially people with little or no medical training who go around diagnosing and treating patients.

In China the designated First Aider at your workplace qualifies as a Doctor. They may even be over-qualified by Chinese standards.

Herd Immunity.

What other nations, particulary ones with signficant outbreaks, need to do now is widespread testing. In order to collect data and publish their own studies similar to the Chinese one. Allowing us to compare the results. Increasing our knowledge and understanding.

I think these future studies should pay particularly attention to people who are asymptomatic. That is to say who are infected with 2019nCoV but don't experience any symptoms. This is an important group that will be entirely missed if people with symptoms are the only ones being tested.

I have heard it said that as many as 35% of infected people are asymptomatic.

However I have no idea as to the source of that statistic. Let alone the validity of the methodology at which it was arrived.

So I am not prepared to recite that as though it is fact.

It is though something which is consistent with what we know about the behaviour of other Coronaviruses. Also from the speed with which 2019nCoV is spreading it is clear that there are infected people wandering about with no idea that they are infected. After all if you're not experiencing symptoms why would you assume you are infected?

I think particular attention should also be paid to whether the human body develops immunity to 2019nCoV. Along with how long that immunity last for.

What happens with most other viruses is that the body stores, almost, blueprints of the antibodies needed to defeat it. So the next time the virus enters the body the right antibodies are immediately produced and the virus is defeated before it can gain a foothold.

Typically those antibody blueprints are stored for life.

I have heard some ancedotale evidence from China that this might not be the case with 2019nCoV. There have been stories of people who have recovered from the virus becoming reinfected.

However there is strong reason to believe those reports are either inaccurate or not telling the complete story.

The second most important job the lungs perform is expelling waste from the body. When you burn fat and lose weight it actually leaves the body through the lungs.

So if some virus cells have travelled to other parts of a persons body it may take some time for them to exit through the lungs. Where they would be picked up in a throat swab test.

Also virus can lay dormant within the lungs for a very long time. Back in January 2019 I suffered Influenza. I swear it took until around November 2019 for all the crap to finally leave my lungs. If I'd undergone a throat swab then I probably would have tested positive for Flu.

Then of course there are some people who are just a bit odd. What is true of the entire rest of the human race is simply not true for them. For example there are actually an extremely tiny minority of people who are born with a natural immunity to the Human Immunodeficiency Virus (HIV). Obviously you do not develop immunity to a virus which destroys the immune system

If it is true that humans develop a lifelong immunity to 2019nCoV and that 35% of infected people do not experience symptoms it completely changes how we respond to the virus.

Right now what everybody is focused on is stopping people from getting infected. Or at least slowing down the rate at which people get infected.

If a large proportion of people experience no symptoms and then become immune we need to be doing the complete opposite. Actively trying to get as many people infected as quickly as possible.

If 87% of the population become immune after experiencing either no or just mild symptoms then what's known as herd immunity will quickly eradicate 2019nCoV. With only 13% of the population left to infect the virus quickly runs out of hosts and dies.

This is how vaccination programs work. People are infected with small amounts of an inert virus. Not enough to cause symptoms but enough for the immune system to draw up and store antibody blueprints.

Once enough people have been vaccinated there is nowhere for the virus to survive.

Even as recently as forty years ago Polio used to kill and maim hundreds of thousands of people each year. Now, thanks to herd immunity, it simply doesn't exist in the World anymore. With a handful of exceptions.

Obviously though you would want real, hard data that many people don't experience symptoms and that a lifelong immunity to 2019nCoV is created before adopting that new strategy.

If either part of that calculation are even slightly wrong the results could be utterly catastrophic.

Potentially you could be talking about 2019nCoV infecting and reinfecting people until absolutely everybody is dead.

That though would be highly unusual.


18:15 on 16/3/20 (UK date).

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